I've been getting started tuning in my MS Labs MS2e on my 91 and have an issue that will cause the engine to stall.

I took it out for a quick autotune today. Runs strong to over 7K. Idle hunts around when it is fully warmed up.

It can stall if I rev up to 2,000 or so then pull my foot off the throttle quickly and the revs drop down below 500 (this is while sitting in the garage after the car if fully warmed up and it's idling in the 800s).

On the road if I push in the clutch and coast to a stop sign it maintains idle. I feel like I rev it slightly more now when I let out the clutch to get going again so it won't bog but over all not bad.

It doesn't seem like VE analyze function is able to tune these cells in before the engine stumbles and stalls.

Can I fix this by increasing the numbers in the cells to the bottom and far left (presumably more fuel) or are there some other settings I should look at and where do I find them?

By the way, I've got a VTPS and it is calibrated so that isn't the problem.

 

sounds like you havent tuned well, and youre going too lean at idle.

 

Pretty new at this myself so take with grain of salt. I also had some similar issues and have learned this much: Don't auto tune below about 1500 rpm - set that filter before you start tuning it will just make your idle erratic, watch your manifold air temp - set your gauges so you can monitor this. Get the car idling decent at low MAT. Let it idle in your garage and monitor as MAT increases. Will probably get crappy starting around 120f. Adjust MAT table as temps increase to stabilize. Will get worse as temps go up and require more correction. My curve now looks crazy but car behaves now. Good luck!

 

I started with the base tune and did a cold start tune with VE analyze live then when it was warm I did the same in the garage on the regular fuel table revving in neutral in garage and letting it idle. I haven't actually changed any of the cells on my own.

I figured that my idle tune was OK since I could come to a stop without stalling and stumbling but sounds like I've got to adjust those lower cells.

 

Thanks for the tip. I'll have to look into how to block certain cells from autotuning.

 

Just go to the advanced tab under the VE analyse tab. Set min RPM to 1500. I also recommend checking the min fuel load setting so it doesn't tune cells you pass through when you're off throttle.